Page tree

Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...


LaTeX Math Block
anchorSw
alignmentleft
\frac{ds_w}{dt} =\frac{1}{A_e \, h_e \, \phi_e(p)} \left[ q^{\downarrow}_w(t) - q^{\uparrow}_w(t) + q^{\downarrow}_{WAQ}(t) \right] -  \left[ c_r(p) s_w +c_w(p) s_w  \right] \frac{dp}{dt}



LaTeX Math Block
anchorSo
alignmentleft
\frac{ds_o}{dt} =\frac{1}{A_e \, h_e \, \phi_e(p)} \left[ q^{\downarrow}_o(t) - q^{\uparrow}_o(t) \right] -  \left[ c_r(p) s_o +c_o(p) s_o  \right] \frac{dp}{dt}



LaTeX Math Block
anchorSg
alignmentleft
\frac{ds_g}{dt} =\frac{1}{A_e \, h_e \, \phi_e(p)} \left[ q^{\downarrow}_g(t) - q^{\uparrow}_g(t) + q^{\downarrow}_{GC}(t) \right] -  \left[ c_r(p) s_w +c_g(p) s_g  \right] \frac{dp}{dt}



LaTeX Math Block
anchor1s
alignmentleft
s_w + s_o + s_g = 1


...

In practice there is no way to measure the external influx 

LaTeX Math Inline
bodyQ^q^{\downarrow}_{GC}(t)
 and 
LaTeX Math Inline
bodyQ^q^{\downarrow}_{AQ}(t)
 so that one need to model them and calibrate model parameters to fit available data on production flowrates history and formation pressure data records. 

There is a list of various analytical analytical Aquifer Drive and  Gas Cap Drive drive models  models which are normally based on the relationsrelated to pressure dynamics 

LaTeX Math Inline
bodyp(t)
:

Gas Cap Drive @model Aquifer Drive @model


LaTeX Math Block
anchor1
alignmentleft
Q^
q^{\downarrow}_{GC}(t) = 
F
q^{\downarrow}_{GC}(p(t))



LaTeX Math Block
anchor1
alignmentleft
Q^
q^{\downarrow}_{AQ}(t) = 
F
q^{\downarrow}_{AQ}(p(t))


which closes a set of equations 

LaTeX Math Block Reference
anchorSw
LaTeX Math Block Reference
anchors
 for the pressure 
LaTeX Math Inline
bodyp(t)
 and saturations 
LaTeX Math Inline
body\{ s_w, \, s_o, \, s_g \}
.


Variations

...


In some specific cases equation 

LaTeX Math Block Reference
anchorMatBal
can be explicitly integrated:

...

Petroleum Industry / Upstream /  Production / Subsurface Production / Field Study & Modelling / Production Analysis / Material Balance Analysis (0D or MatBal)